Add new form fields to signup form. Want to store more info.

I would like to add more form fields to the signup page. I want to store these new fields in the database as well. I just want to add the fields FullName and JobTitle and maybe one or two more things. I have been looking around in all of the files and cannot
figure out how to add these fields into the form or to put them into the database.

I have taken over this website and did not initially set it up. So I have no idea where to look to add these fields.

I'm pretty sure that they are using MS SQL database, but I have no idea where the core library is and where to edit the db provider class.
As for the login screen, I have the code point to a CreateUserWizard1 and I cannot find where the code for the form is? I'm not great with aspx but I understand the code and I know that it's pulling the form from somewhere else. I thought this was universal
across BlogEngine because I cannot find it in any user files. So I figured it was in some library file that was predefined.

Also, like I said, I am taking over this site and I wasn't the person who set it up, nor is he around. So I am basically out to lunch without a sandwich right now.

I seriously am drawing blank on this one. I definitely need someone to give me some help. I looked at that link in the post by rtur and that obviously looks like where I need to be. But that file does not exist on my server. Either that or it's hiding on
me. The DotNetSlave.BusinessLogic is the only directory that I see this file exists in. I do not have that directory on the server I am working on. I understand .aspx poorly but I definitely understand the DbMembershipProvider.cs and would have minor difficulty
changing it, but I have no clue where it is. Is it possible that a previous version did not use this class.

BlogEngine consists of 2 projects, web site and class library. Once compiled, class library (DotNetSlave.BusinessLogic files) becomes BlogEngine.Core.Dll and copied into "bin" directory in your web app. So you need to have access to full source
code, both projects. Make changes to that class file, build it in Visual Studio and it will update "bin" with newly compiled Core.dll - that what you'll need to copy to your server.